In golf, as in other sports, it is desirable that the golfer be able to repeat the ideal swing in order to achieve superior results. Likewise, in baseball the batter desires to repeat the ideal swing, or a prior successful swing in order to achieve optimum results when hitting the ball.
Similarly, in target practice for archery or shooting, it is desirable to provide an ideal head position in order to obtain repeatable success.
There have been various prior art devices which assist an athlete in this regard. U.S. Pat. No. 3,860,246 discloses a device for aiding a golf player in addressing the ball and maintaining a stance during the backstroke and forward stroke. The device includes a mouthpiece with a plumb-bob weighted body suspended therefrom via a flexible cord. During the backstroke and forward stroke of the golf club, the user can immediately visually notice movement of the user's head by movement of the weighted body.
U.S. Pat. Nos. 4,869,509 and 5,108,104 disclose a mercury switch for detecting when the head of the golfer is aligned within a certain orientation. The devices are positioned at the golfer's head.
U.S. Pat. No. 4,502,305 discloses a golfer's head motion sensor having a piezoceramic bender element a cantilevered position to a plate wherein vertical and side-to-side head movement of the golfer is detected and produces signals in electrical leads attached to opposite sides of the piezoceramic bender element. The electrical signals are processed and provide an indication to the golfer of movement acceleration. The motion sensor is worn upon a golfer's cap.
Certain of the prior art devices are cumbersome and expensive to manufacture. In addition, the motion information provided to the user is crude and somewhat inaccurate as well as limited in terms of the one-dimensional indication of the movement of the head.